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A new bis-TTF donor (TTF is tetrathiafulvalene) containing a pyridine diester spacer, namely bis{2-[(6,7-tetramethylene-3-methylsulfanyltetrathiafulvalen-2-yl)sulfanyl]ethyl} pyridine-2,6-dicarboxylate-tetracyanoquinodimethane-dichloromethane (2/1/2), 2C(33)H(33)NO(4)S(12) x C(12)H(4)N(4) x 2 CH(2)Cl(2), has been synthesized and its electron-donating ability determined by cyclic voltammetry. The electrical conductivity and crystal structure of this donor-acceptor (DA) complex with TCNQ (tetracyanoquinodimethane) as the acceptor are presented. The TCNQ moiety lies across a crystallographic inversion centre. In the crystal structure, TTF and TCNQ entities are arranged in alternate stacks; this feature, together with the bond lengths of the TCNQ molecule, suggest that the expected charge transfer has not occurred and that the D and A entities are in the neutral state, in agreement with the poor conductivity of the material (sigma(RT) = 2 x 10(-6) S cm(-1)).

2C 10 H 8 S 8 + •Mo 6 O 19 2− cristallise dans P2 1 /c avec a=8,898, b=11,265, c=21,098 A, β=96,34 o , Z=2; affinement jusqu'a R=0,036. 2C 10 H 8 S 8 + •W 6 O 19 2− cristallise dans P2 1 /c avec a=8,908, b=11,310, c=21,111 A, β=96,37 o , Z=2. La liaison C=C centrale (1,388 A) et les deux types de liaisons C−S (1,720 et 1,737 A en moyenne) du BEDT-TTF sont en bon accord avec celles de molecules totalement oxydees. Observation de contacts inter-dimeres et intra-dimeres courts

The central C=C bond length [1.391 (9) A] and the two types of C-S bond lengths [average 1.712 (6) and 1.735 (7) A] of the DMDPh-TTF (C 20 H 16 S 4 ) molecule compare well with those observed for the fully oxidized species. This organic molecule has a trans configuration. The phenyl rings are not coplanar with the central TTF fragment. The dihedral angles observed between the phenyl rings and the central TTF core are 38.1 (2) and 50.9 (2) o . There are no interactions between the organic molecules since the intermolecular S...S contacts are greater than 4 A. The shortest S...O contacts observed are: S(1)...O(6) 3.217 (5), S(2)...O(4) 3.296 (5) and S(3)...O(3) 3.298 (5) A

The two compounds (DMTTF)ReO 4 (1) [DMTTF=2-(1,3-dithiol-2-ylidene)-4,5-dimethyl- 1,3-dithiole cation] and (CHDTDMDSF)PF 6 (2) [CHDTDMDSF=2-(4,5-dimethyl-1,3-diselenol-2-ylidene)-4,5,6,7-tetrahydro-1,3-benzodithiole cation] contain unsymmetrically substituted tetrathiafulvalene (TTF) derivatives. They present similar crystal structures which are characterized by alternating organic dimers and inorganic pairs of anions. The values of the central C-C bond lengths are 1.39 (1) and 1.40 (1) A for (1) and (2), respectively

Cristallisation dans Pī avec a=7,8665, b=7,8575, c=13,4458 A, α=95,67, β=101,36, γ=111,08°, z=2; affinement jusqu'a R=0,0489. Les cations organiques DMCTTF + s'empilent le long de l'axe a, selon un mode de type zigzag. Ils forment des colonnes conductrices de dimeres faiblement lies. Les anions AsF 6 - sont localises dans les cavites, laissees par les molecules organiques. Les atomes As sont situes sur le centre d'inversion de leur octaedre